Typewriter



2 Sheets-Sheet l J. A. LA HIFF TYPEWRITER Filed May 9. 1956 'II Ill llllll llllllllli INVENTOR. ./0//4/ 67. 19 MPF m@ ATTQRNEYS May 2, 1939.

J. A. LA HIFF May 2, 1939.

TYPEWRITER 2 Sheets-Sheet 2 Filed May 9, 19156 Patented May 2, 1939 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to typewriters and similar machines, and refers more particularly to means for adjusting the speed of the movable carriage of a typewriter.

An object of the present invention is the provision of conveniently located and easily operable remote control for the tension of the main spring of a typewriter, through the use of which the speed of movement of the carriage may be ad- 1o justed by an operator to suit his individual requirements.

Another object is the provision of inexpensive and durable adjusting means, through the use of which the speed of a typewriter carriage and l the force which must be applied to the typewriter keys may be varied within predetermined limits.

The above and other objects of the present invention may be realized through the provision of a speed control unit comprising a supporting member mounted upon an element of the carriage frame and movable along with the carriage, the position of said supporting member upon the carriage frame being adjustable by a simple clamping device, a guide mechanism or the like.

The drawband which pulls the carriage in the course of the typewriting is attached to said supporting member, the opposite end of the drawband being connected with a spring in the usual manner.

In accordance with a modified form of the inventive idea, the speed of the carriage may be varied by adjusting the tension oi the spring operating the drawband which is connected with the carriage.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing preferred embodiments of the inventive idea.

In the drawings:-

Figure-1 is a top view of a part of a typewriter provided with adjusting means constituting the subjectmatter oi" the present invention;

Figure 2 is a section along the line 2--2 of Figure 1;

Figure 3 is a rear view of a portion of the device shown in Figure 1,1ooking in the direction of the arrow 3 in Figure 2;

Figure 3a, is a section along the line 3cr- 3a. of Figure 3, on an enlarged scale;

Figure 4 illustrates a modified form of the drawband supporting means;

Figure 5 is a rear view illustrating a portion 55 of a typewriter provided with adjusting means Cl. IS7- 62) oli1F a somewhat diiierent type with parts broken 0 Figure 6 is a side view, looking in the direction off the arrow 6 of Figure 5, with some parts broken 0 Figure 7 shows partly in section and partly in s1de elevation a device for adjusting the tension of the spring operating the drawband of a typewriter; and

Figure 8 is a section along the line 8-8 of 10 Figure '7.

The typewriter illustrated in. Figures 1 to 3a. of the drawings may be of any standard or other make and comprises a frame IIJ supporting the structure of the typewriter and provided With a 15 front shield portion I I. The member I8 situated in front ofthe movable carriage I4 serves as a guide for the type bars which are not shown in the drawings.

The framerl carries two parallel tracks or guides I2 and I3 along which the carriage I4 is moved. A frame member I5 which is situated below the guide tracks I2 and I3 carries an axle 34. A reel I6 is rotatably mounted upon the axle 34 and is connected with the end Il of a draW- band 33. A coiled spring 53 (Figure 2) is situated within the reel I6, the inner end of the spring being connected with the axle 34, while the outer end of the spring 53 is attached to the reel I6.

The carriage I4 which is reciprocable upon the 30 guide tracks I2 and I3 comprises supports or flange portions I9 and 20 cooperating with the guide tracks I3 and I2, respectively (Figure 2). The carriage I4 is carried by ball bearings 2l and 22 which are situated between the flange 3- portions I9 and 20, on the one hand, and the guide tracks I3 and I2, on the other hand.

The platen 23 of the carriage is supported at both ends by vertical frame elements 24 and 25, which are carried by the supports I9 and 20 and are connected with each other by horizontal bars 26 and 21.

The platen 23 is i'lrmly connected with a toothed wheel 28 which cooperates with a pawl 29 in the usual manner. The shaft 30 of the platen 23 which passes through suitable openings formed in the vertical frame elements 24 and 25 is provided at both ends` with handles 3l and 32 so that the platen 23 may be rotated one tooth at a time.

The escapement mechanism causing the movement of the carriage I4 may be of any standard construction and is not illustrated in the drawings. When the operator begins to Write a new line on the typewriter he rst moves the carriage 55 I4 to the right (looking in the direction of Figure l). The end 36 of the drawband 33 is connected with the movable carriage I4 by an adjusting device 31 which will be described in detail hereinafter. The other end I1 of the drawband 33 is wound around thereel I 6 and is rmly attached to the reel. When the carriage I4 is moved by hand all the way to the right along the guides I2 and I3, it pulls the drawband 33 with it, so that the drawband unwinds itself from the reel I6 and rotates the reel, thereby increasing the tension of the spring 53 situated within the reel I6.

As soon as a key is depressed the escapement mechanism which is not shown in the drawings frees the carriage I4 to the extent of one letter space. The wound spring 53 situated Within the reel I6 is permitted to unwind itself to that eX- tent, so that it winds the end I1 of the drawband 33 upon the reel I6 and pulls the carriage I4 in the direction of the arrow 35 to the extent of one letter space.

The described mechanism of the typewriting machine is of standard make and does not constitute a part of the present invention.

The present invention is concerned with the provision of means enabling the operator to adjust the tension of the spring 53 situated within the reel I6, thereby varying the speed with which the carriage I4 is moved by the drawband 33 at each depression of a key. Furthermore, since the escapement mechanism which is not shown in the drawings provides a frictional engagement between the movable carriage and its support, the speed of travel of the carriage is also a function of the force with which each individual key is depressed. When the speed of travel of the carriage is comparatively great, the force with which a key is depressed must also be a heavy one. On the other hand, if a carriage moves rather slowly, the force with which a key must be depressed to cause the movement of the carriage may be comparatively light.

In accordance with the present invention, the typewriting machine is provided with an adjusting device 31 (Figure 3), which carries the end 36 oi the drawband 33, which is movable along with and constitutes a part of the carriage I4, and which at the same time may be adjusted relatively to the carriage. Through the use of this device the speed of the carriage I4 and the force necessary to strike a key, may be adjusted by an operator to suit his individual requirements.

The device 31 is mounted upon the horizontal bar 26 constituting a part of the carriage and comprises a U-shaped rider or supporting member 38 having ears 39 interconnected by a pin 45 to which the end 36 of the drawband 33 is attached.

That portion of the bar 26 which carries the adjusting device 31 has a number of teeth 40 with which the bar 46 of an outer U-shaped casing 42 is in engagement. The U-shapedpcas- .ing 42 is pivotally connected at 43 with the rider 38 and carries a knob 41. A spring 44 is situated between the rider 38 and the casing 42 adjacent the knob 41.

In the position shown in Figure 3 the spring 44 presses the U-shaped casing 42 upwardly, thereby pressing the bar 46 against the teeth 40 and thus clamping the adjusting device 31.

In order to shift the device 31 along the bar 26, the operator merely has to press the knob 41 downwardly, thereby compressing the spring 44 and releasing the engagement of the bar 46 With the teeth 40. Then the device 31 can be easily moved along the bar 26 to any new posi tion, to increase or decrease the tension of the spring 53 situated within the reel I6.

Preferably, a portion of the drawband 33 is situated within a U-shaped hollow tube 48, the upper end of which is supported by a sleeve 49 carried by the bar 26. Due to this arrangement, the drawband 33 is always supported in its proper position and there is no danger that it will slip off, or become loose.

In the modied form illustrated in Figure 4, the bar 26 carries a sleeve or other similar member 50 which is provided With a rotatable Wheel 5I. Another wheel 52 is situated under the wheel 5I. The drawband 33 may be passed over the wheels 5I and 52 and may be guided by these Wheels in lieu of the U-shaped tube 48 illustrated in Figure 3.

As shown in the drawings, the movable adjusting device 31 carried by the horizontal bar 26 of the carriage I4 is situated substantially in the rear of the typewriter and is easily accessible to an operator. As soon as an operator nds that in his opinion the movement of the carriage is too fast or too slow, or that he is required to apply too much or too little pressure upon the keys in order to cause a type to strike the paper covering the platen 23, he shifts the adjusting device 31 along the bar 26 until the tension of the spring 53 causing the movement of the carriage is adjusted in accordance with his requirements. The bar 26 may be provided with any suitable inscriptions or a scale not shown in the drawings which would assist the operator in carrying out the desired adjustment.

The device shown in Figures 5 and 6 of the drawings comprises a typewriter frame 60 carrying guides 6I and 62 supporting a movable carriage 63 which is provided with ange supports 64 and 65. Ball bearings 66 are situated between the flange support 64 and the guide 6I, while the ball bearings 61 are situated between the ange support 65 and the guide 62. The carriage 63 of the typewriter comprises a platen 61 having a handle 68 and supported by vertical frame members 1l) which are carried by a horizontal lower support 12 connected with the iiange members 64 and 65. A horizontal bar 13 extends parallel to the support 12 and is carried by the vertical frame members 1D, only one of which is shown in the drawings.

When one of the types has struck the writing paper covering the platen 61, the carriage 63 is moved by means of a drawband 14, one end of which is attached to the rotatable reel 15, while its other end is attached to an adjusting device 16 mounted upon the support 12 of the movable carriage 63.

A coiled spring 11 shown by broken lines in Figure 6 is situated within the rotatable reel 15. One end of the coiled spring 11 is rmly connected with the reel 15, while its other end is rmly attached to the axle upon which the reel 15 is mounted and which is not shown in the drawings.

'Ihe adjusting device 16 comprises a bolt 18 which passes through an opening 19 provided in the lower portion of the vertical support 16. Ihe bolt 18 is carried by two supports 88 and 8I mounted upon the support 12 of the carriage and is provided with a handle portion 82 by means of which it can be conveniently turned by the operator. A nut 83 provided with inner threads is mounted upon the threaded portio'n 84 of the bolt 18. The nut 83 has an extension or ear 85 to which the end 86 of the drawband 14 is attached.

In order to adjust the tension of the spring 11 situated Within the reel 15, it is necessary to turn the bolt 18, thereby causing the nut 83 to move along the threaded portion 84 of the bolt 18. Since every change in the position of the nut 83 will cause a change in the tension of the spring 11, the operator will be able to adjust the speed of movement of the carriage 83 to suit his individual needs merely by turning the handle portion 82 of the bolt 18.

The device illustrated in Figures '1 and 8 of the drawings comprises a frame of the typewriting machine to which a bracket 9| is attached. The bracket 9| carries an axle 92 upon which is mounted a rotatable reel 93. A coiled spring 94 is situated within the reel 93, one end of the spring being firmly attached to the axle 92. The opposite end of this spring 94 is firmly connected at 95 to the reel 93. A drawband 96 is also connected to the reel 93. The opposite end of the drawband is connected to a typewriter carriage which is not shown in the drawings.

The device used for adjusting the tension of the spring 94 comprises a lever 91 having an annular portion 98 which is mounted upon the axle n of teeth |82 which are adapted to engage a resilient member |03 carried by the lever 91. Since the axle 92 is rotated along with the lever 91 and since one end of the spring 94 is attached to the axle 92, a rotation of the lever 91 will increase or decrease the tension of the spring 94, thereby changing the speed of movement of the typewriter carriage which is connected by the drawband 9G and the reel 93 with the spring 94. The lever 91 is held in the selected position by the resilient member |83. The segment |80 may be provided with any suitable inscriptions to enable the operator to adjust the tension of the spring 94 without any preliminary experiments.

What is claimed is:

In typewriting machines, in combination with a movable carriage frame, a spring for moving said frame, and a drawband adapted to be actuated by said spring; a bolt carried by said frame and having a threaded portion, said bolt being movable along with said frame, and a nut mounted upon the threaded portion of said bolt and carrying an end of said drawband.

JOHN A. LA I-IIFF. 

